Bike Talk Motorcycle Forum Bike Talk Motorcycle Forum
Go Back   Bike Talk Motorcycle Forum > The Garage > Motorcycle Tech Talk
Discussion on Is dyno tuning really any good ?? within Bike Talk's Motorcycle Tech Talk forum.

Home Forum Register FAQ Sponsorship Search Today's Posts Mark Forums Read

Is dyno tuning really any good ??


Welcome to the Bike Talk motorcycle forum Contact Bike Talk Join Bike Talk

» Site Navigation
 > F.A.Q.
» Auction

» B-T Recommends:
Visit Biker Bids

Harley-Davison Parts & Accessories at RideGear.com


Reply
 
Old Sep 24th, 2006, 09:42 PM   #1
Tomflhrci98
200+ posts and climbing
 
Tomflhrci98's Avatar
 
Join Date: Aug 2004
Posts: 365
View Tomflhrci98's Gallery
23 Images Posted

I finally got my engine back into the Road King. After I but on an easy 500 miles on it I brought it back to my engine rebuilder to do the dyno tuning work. This was something I have been dying to watch. I have always had my doubts about how effective an inertia dyno can be for a complete map adjustment.

My doubts where confirmed. I watched as they made about 6 WOT runs from 2000 rpm to 5500 rpm. They produced some pretty power and torque curves, but the only changes they did between each run was download 6 different pre-made curves from the Power Commander map list. They picked the best one and called it good. I never saw their AFR meter go below 22. I new it was going to be up to me to get the bike to run right and I was going to have to do it with out an AFR meter.

I want to go to another “dyno expert” and find if there is someone who can really calibrate a complete RPM vs. Throttle position fuel and spark map on a dyno. These are the things that I think you would need;
1. An electric dynamometer – An electric dyno can hold a speed as you check all of the throttle positions on the map, such as 20%, 40%, 60%, etc. at one speed then change to another speed on the map. I am sure this type of dyno is too expensive for most shops. Has anyone ever seen one of these?
2. An air fuel ratio (AFR) meter that actually works. Perfect AFR for gasoline is 14.7 to 1, but at WOT it should be richer, like 11 or 12 to 1, not 22 to 1 like I mentioned above.

With proper equipment I believe you could actually do this in a couple of hours. In my engine rebuilder’s defense I will have to admit that his claim to fame is drag racing. So the WOT runs make some sense cause they don’t care about anything else. But, most of us on this forum are not drag racers, we’re cruisers. We need crisp throttle response, no pinging on hot days, no coughing thru the air cleaner when you are trying to pull out in traffic, etc.

Now I got a beef about these “pre-made” maps that are on the Power Commander disk. Why is there no uniformity to any of these maps? How can they go from adding 11% fuel at one point and then subtracting -8% in the cell right next to it? This does not make an sense. I am sure that from the multitude of ours spent on an engine dyno at Harley-Davidson Engineering Department that they came up with a smoother base map than that to work from. I have to believe that when we make changes like changing exhaust pipes or camshafts that these things affect the whole engine map in a uniform manner. I am not saying that it is the same everywhere on the map. I am sure air flow will be better at some points then others due to these changes but the air flow can’t be as erratic as I see in these maps supplied by Power Commander. Has anyone else come up with a smoother looking map for their bike? I am just curious how other people are doing with mapping their own engines.
Tomflhrci98 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Sponsored Links
Old Sep 25th, 2006, 01:40 PM   #2
CD
Administrator
Has posted 500+
 
CD's Avatar
 
Join Date: Mar 2004
Location: Tucson AZ
Posts: 1,563
Interests: Fishing, wood working, flipping off Fred Fox
Occupation: Founder of Bike Talk....retired and lovin' it
On a carbureted bike and inertia dyno helps for tuning because you can simulate WOT plug chops and read the plugs. On EFI bikes, an inertia dyno is about useless for anything more than giving you WOT max HP and Torque values.

EFI bikes require a load cell dyno such as the Dynojet 250I.

http://www.dynojet.com/motorcycle_dy...yno/index.aspx

Using a load cell dyno and a tuning device like the Power Commander USB allows the technician to create a custom map with AF Ratios as close to optimum as possible. The caveat to that is that a really good tuner knows where to add or remove fuel and or timing to insure the mixture is not too lean to prevent proper cooling.

These load cell dyno's aren't cheap at over 25k and to be an authorized tuning center you must have six months experience on the 250I and attend a class at Dynojet.

There are several tuning centers in CA
http://www.powercommander.com/centers_ca.shtml

"Now I got a beef about these “pre-made” maps that are on the Power Commander disk. Why is there no uniformity to any of these maps? How can they go from adding 11% fuel at one point and then subtracting -8% in the cell right next to it? This does not make an sense. I am sure that from the multitude of ours spent on an engine dyno at Harley-Davidson Engineering Department that they came up with a smoother base map than that to work from. I have to believe that when we make changes like changing exhaust pipes or camshafts that these things affect the whole engine map in a uniform manner. I am not saying that it is the same everywhere on the map. I am sure air flow will be better at some points then others due to these changes but the air flow can’t be as erratic as I see in these maps supplied by Power Commander. Has anyone else come up with a smoother looking map for their bike? I am just curious how other people are doing with mapping their own engines."

These "pre-made" or "canned" maps are the result of testing with that configuration at Dynojet and are not just something an engineer puts together. Why do the cells vary so much? Because an exhaust does not flow the same CFM at every throttle and RPM setting. If you were to look at the flow test charts of an exhaust it will look not have a uniform flow across the RPM range. At some point every exhaust has some reversion characteristics. Every system will flow better at one RPM than another. In order to get the tuning right you have to vary the AFR and sometimes the timing. Another thing to consider is that you are not seeing the HD map in the ECU so you have no idea what it's cell is reading. If you have 10 cells the ECU map may be up and down cell to cell. The Power Commander cells use that cell as a reference and using it's parameters will add or reduce fuel as needed. The maps are developed on the 250I that performs the functions you describe.
CD is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old Sep 25th, 2006, 02:33 PM   #3
hotroadking
Has posted 500+
 
hotroadking's Avatar
 
Join Date: Jun 2004
Posts: 2,034
The thing you need to do is learn the questions to ask the tuner, if you get some bs or "I don't need to do it that way" answer, walk away.

With an EFI bike you need the correct dyno to tune it properly, Carls in Daytona is one of the best with Powercommanders and EFI, but Carl is a jerk, his son is cool and that's who you should talk to, avoid Carl, if you don't buy the parts there he'll piss you off. But don't worry about him, big bark no bite.

A custom map will take about 2 hours and it will require about $250.

John Golden is very good with EFI and Carbs, and he travels from event to event.

He may upload a base map that he knows works with your pipe and cams and tune it from that starting point.

CD told you alot of the items you need to know. Check around in your area for someone that knows tuning EFI bikes. I know you're in CA so you need to find a local shop that is top notch in EFI in your area, call Dynojet, let them know you want a custom map made and where to go in LA.
hotroadking is online now  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old Sep 25th, 2006, 04:23 PM   #4
Tnicean
Rookie 10+ posts
 
Join Date: Dec 2005
Posts: 21
My dyno tune included an AF ratio across the rpm ranges. It is pretty flat at somewhere between 13 & 14. I only have the stage 1 with a stock ECM and the bike (2002 Heritage Softail Classic) has a really good torque curve and max numbers of 77HP and 83 ft/lb torque. I am in Richmond, Va and I used the Dyno tune shop listed on the website. It was $200 and I was well pleased with the results. I have over 8K miles on the tune and the bike runs great with only a blurby blurb gurgle gurgle under rapid de-acceleration. No real popping or backfiring. I don't have my print out in front of me or I would give the exact numbers. I have the BSS and Ness Big Sucker that I purchased here and installed them myself.
Tnicean is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Old Sep 25th, 2006, 05:28 PM   #5
Tomflhrci98
200+ posts and climbing
 
Tomflhrci98's Avatar
 
Join Date: Aug 2004
Posts: 365
View Tomflhrci98's Gallery
23 Images Posted
Well CD, I stand corrected. I am glad to see that Power Commander spent some time on these. I was under the impression that they came from different sources.

I see the 250i load control dyno is the ticket. Thanks for the links. That is a very nice web site w/quick access to road map locations of test sites. I should have done a little more research.

I am used to doing calibration on V8’s so the exhaust reverb problem must be a lot more pronounced with the V2’s. This makes sense now that I think about it.

They other thing I was dealing with was the area around 2000/3000rpm and 40/70% throttle. My bike was pinking like crazy and I added a lot of fuel in this area (as much as 22%) and took out 5 degrees in a couple of cells and I may have to take out more.

This may be due to the fact that we shaved the heads and I don’t see any maps for higher compression EVO’s. I had the a Power Commander before and didn’t need that much fuel change. Now, after the rebuild, it definitely needs the PC.

Then I blended the map in to the 2000rpm and above and 0/10% throttle area to get rid of back fire and induction cough. The bike runs nice but who really knows what the AFR is. So with all the changes I did - I basically through out the M801-320.djm map I started with.

I may have to break down and go to one of the dyno centers. I'll call Pomona tomorrow.

Thanks,

98 EVO, Red injectors, Andrews 27 cam, K&N, Stage 2 ECM burn, Shaved heads.
Tomflhrci98 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply

«- How much will I loose? « Previous | Next » brakes on 85 fxrs -»



Thread Tools



Similar Threads to: Is dyno tuning really any good ??
Thread Thread Starter Forum Replies Last Post
Flexible tuning device????? mtnrider Motorcycle Tech Talk 5 Dec 21st, 2005 07:12 AM
Texas Power Commander Dyno tuning AFNurse Pull up a chair and sit for a spell 0 Aug 22nd, 2005 08:28 PM
EFI Tuning roadking00 Motorcycle Tech Talk 13 May 8th, 2005 08:55 AM
Mikuni 42 tuning Devil Dog 84 Motorcycle Tech Talk 3 Apr 7th, 2005 10:25 AM
Dyno Tuning AFNurse Motorcycle Tech Talk 6 Mar 10th, 2005 08:14 PM

Powered by vBadvanced CMPS v3.0 RC1

All times are GMT -7. The time now is 04:59 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.0.0 RC8
BikeTalk Motorcycle Forum Copyright 1997-2009 all rights reserved


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107